User-based redesign after implementation has been studied in manycontexts gone by many different names, such as appropriation of technology,malleable design and secondary design. The phenomenon of redesigning contenthas mainly revolved around technologies such as Facebook, Twitter, orWikipedia or portal-based technology with configuration abilities, with very littlefocus on technologies where users can change both functionality, contentand the level of technology complexity. We coin this type of secondary designdeep secondary design. In this paper, we investigate how to enable deep secondarydesign by analyzing two cases where secondary designers fundamentallychange functionality, content and technology complexity level. The first caseredesigns a decision model for agile development in an insurance company; thesecond creates a contingency model for choosing project management tools andtechniques in a hospital. Our analysis of the two cases leads to the identificationof four principles of design implementation that primary designers can apply toenable secondary design and four corresponding design implementation principlesthat secondary designers themselves need to apply.